Methods and apparatus to detect audio engineering problems using identification of isolated watermarks

ABSTRACT

Example methods and apparatus to detect audio engineering problems using identification of isolated watermarks are disclosed herein. Disclosed example methods include identifying, by executing an instruction with a processor, isolated watermarks in a first set of detected watermarks obtained from first media monitored at a first site. Disclosed example methods further include determining, by executing an instruction with the processor, a problem has been detected with the first media associated with the first set of detected watermarks in response to a first number of isolated watermarks identified in the first set of detected watermarks satisfying a first threshold.

FIELD OF THE DISCLOSURE

This disclosure relates generally to improving media transmission and,more particularly, to methods and apparatus to detect audio engineeringproblems using identification of isolated watermarks.

BACKGROUND

For many years, media undergoing transmission has included watermarks.Watermarks are embedded in the media outside the perception of theviewer. Audience measurement entities use the detection of watermarks toidentify a source and/or ownership of presented media.

Watermarks embedded in transmitted media may repeat regularly throughoutthe duration of presentation. The watermarks are often repeated atregular intervals to improve accuracy of collected data and eachwatermark may include an identification and a timestamp.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example media monitoring system including a mediamonitoring site for detecting broadcasted watermarks

FIG. 2 illustrates an example media monitoring system including a meterfor detecting presented watermarks.

FIG. 3 illustrates an example audience measurement system for detectingwatermarks embedded in broadcasted media.

FIG. 4 illustrates an example block diagram of a watermark.

FIG. 5 illustrates an example audio signal including an embeddedwatermark.

FIG. 6 illustrates an example block diagram of information conveyed inan example embedded watermark.

FIG. 7 illustrates an example block diagram of an example meter todetect watermarks.

FIG. 8 illustrates an example block diagram of an example audiencemeasurement entity processing example watermark data.

FIG. 9 is a histogram of example detected watermark collection data.

FIG. 10 is a flowchart representative of example computer readableinstructions that may be executed to implement the example meter of FIG.7

FIG. 11 is a flowchart representative of example computer readableinstructions that may be executed to implement the example audiencemeasurement entity of FIG. 8.

FIG. 12 is a block diagram of an example processor platform structuredto execute the example computer readable instructions of FIG. 10 and theexample meter of FIG. 7.

FIG. 13 is a block diagram of an example processor platform structuredto execute the example computer readable instructions of FIG. 11 toimplement the example audience measurement entity of FIG. 8.

The figures are not to scale. Wherever possible, the same referencenumbers will be used throughout the drawing(s) and accompanying writtendescription to refer to the same or like parts.

DETAILED DESCRIPTION

Watermarks are embedded in a variety of audio/visual media. For example,broadcasters, such as television broadcasters, radio broadcasters, cabletelevision providers, satellite television providers, etc., embedwatermarks in the broadcasted media. As such, watermarks are embedded inmedia, such as news, televised dramas, movies, etc., transmitted by thetelevision station broadcaster, and are received at a media presentationsite such as a home or business.

In some examples, an audio watermark is embedded in a news broadcasttransmitted to a presentation site. Watermarks transmitted topresentation sites can be detected by a meter utilized by an audiencemeasurement entity for detecting embedded watermarks. For example,watermarks detected by the meter are used by the audience measuremententity to determine what media was presented and for how long the mediawas presented. These watermarks are often repeated at a regular intervalto improve the accuracy of the watermark data being collected.

Audience measurement entities determine what media was presented and forhow long the media was presented based on the detection of watermarks.For example, embedded watermarks in the transmitted media are embeddedas audio, imperceptible to an audience, yet perceptible by a meter. Insuch examples, the meter can detect embedded watermarks and determinethe information contained in the audio signal. Embedded watermarks caninclude information such as, but not limited to, a station identifier(SID), a media identifier, and a timestamp, etc., among other mediaidentifying information.

In some examples, watermarks as transmitted, as received, or aspresented are incorrect (referred to herein as errant watermarks). Inthe past, errant watermarks were removed or ignored in detectedwatermark data. Watermarks can become errant watermarks as a result oftechnical difficulties at the presentation site, problems in thetransmission, or issues related to the embedding of the watermark in themedia. Errant watermarks may not properly identify the stationtransmitting the media, and, in some examples, may be only one errantwatermark among dozens of good watermarks.

Some of these watermarks may be isolated, errant watermarks. Forexample, an errant watermark would be identified as a single isolatedwatermark if, over a short period of time (e.g., 30 seconds, 2 minutes,etc.), only one watermark incorrectly identifies the SID. For example, ameter detects watermarks on channel 1 media being presented at apresentation site for five minutes, but may detect a single watermarkfor channel 2. In such an example, the single watermark identifyingchannel 2 would be considered an isolated watermark (e.g., a single, badwatermark).

In accordance with the present disclosure, the detection of isolatedwatermarks can be used to determine the existence of problems in theengineering, transmission, reception, and/or presentation of media. Theregular and consistent detection of isolated watermarks can, forexample, be indicative of problems with media reception. In someexamples, the problem can be identified as a site-specific problem(e.g., a reception problem), while in other examples, the problem can beidentified as systemic (e.g., a problem with the audio engineering ortransmission).

In some examples, a meter monitoring at a media monitoring site operatesto detect for watermarks embedded in broadcasted media. Consider anexample in which a meter detects an errant watermark every thirtyseconds to a minute over a two-hour period. In such an example, theerrant watermarks are detected and identified as isolated watermarks. Inexamples disclosed herein, the watermark data is evaluated over ameasurement interval and, for example, a histogram of the watermarksdetected is made and the number of isolated watermarks is evaluatedagainst a threshold. If the number of isolated watermarks meets athreshold, the isolated watermarks are attributed to the existence of aproblem with media transmission, reception, or presentation; otherwise,the number of isolated watermarks does not indicate a problem and theisolated watermarks are ignored.

In some examples, meters are located at separate geographic locations.For example, the meters could be located at two media monitoring sites,a media monitoring site and a house, two different houses, or a houseand a broadcasting source, or other locations receiving or presentingmedia. The example meters at the different locations detect watermarkdata. If multiple meters at separate geographic locations are detectingwatermarks for the same media, their reported data can be compared at acentral processing facility, such as an audience measurement entity. Insome examples, one, some, or all of the meters will identify problemswith the watermarks embedded in the media.

In some examples, when just one example media monitoring site amongmultiple media monitoring sites detects a problem with watermarked mediapresentations, the audience measurement entity can, for example,identify the problem as a site-specific problem (e.g., a problem withthe media monitoring system, the meter, etc.). However, if multipleexample meter monitoring sites detect a problem with the samewatermarked media, the example audience measurement entity can identifythe problem as being a systemic problem. In such examples, theappropriate measures can be taken to resolve the problems with the mediabroadcast and/or presentation. Resolving problems in the broadcastand/or presentation of media based on isolated watermarks (e.g., badwatermarks) will improve the fields of media broadcasting and audiencemeasurement.

FIG. 1 illustrates an example media monitoring system 100 including amedia monitoring site 102 for detecting broadcasted watermarks. In theillustrated example of FIG. 1, the example media monitoring site 102includes content receivers 104 a, 104 b, 104 c, 104 d, 104 e, 104 fconnected to meters 106 a, 106 b, 106 c, 106 d, 106 e, 106 frespectively. For example, there is a content receiver for all mediabroadcasted regionally, such as television, cable, satellite, radio,streaming, etc. The example content receivers 104 a, 104 b, 104 c, 104d, 104 e, 104 f receive the media but do not present the media via adisplay screens and/or speakers, however in other examples, the contentreceivers 104 a, 104 b, 104 c, 104 d, 104 e, 104 f are additionallyconnected to media presentation devices (e.g., display screens,speakers, projectors, etc.).

In the illustrated example, the content receivers 104 a, 104 b, 104 c,104 d, 104 e, 104 f receive broadcasted media from media sources 112. Insome examples, each content receiver 104 a, 104 b, 104 c, 104 d, 104 e,104 f receives and processes different media. For example, televisionprograms broadcasted on channel 1 are an assigned media source to bereceived by content receiver 104 a and television programs broadcastedon channel 2 are an assigned media source to be received by contentreceiver 104 b.

The content receivers 104 a, 104 b, 104 c, 104 d, 104 e, 104 f receivemedia from the media sources 112. The media sources 112 may be any typeof media provider(s), such as, but not limited to, a cable media serviceprovider, a radio frequency (RF) media provider, an Internet basedprovider (e.g., IPTV), a satellite media service provider, etc., and/orany combination thereof. The media may be radio media, television media,pay per view media, movies, Internet Protocol Television (IPTV),satellite television (TV), Internet radio, satellite radio, digitaltelevision, digital radio, stored media (e.g., a compact disk (CD), aDigital Versatile Disk (DVD), a Blu-ray disk, etc.), any other type(s)of broadcast, multicast and/or unicast medium, audio and/or video mediapresented (e.g., streamed) via the Internet, a video game, targetedbroadcast, satellite broadcast, video on demand, etc. For example, thecontent receivers 104 a, 104 b, 104 c, 104 e, 104 f can correspond to areceiver that supports the National Television Standards Committee(NTSC) standard, the Phase Alternating Line (PAL) standard, the SystèmeÉlectronique pour Couleur avec Mémoire (SECAM) standard, a standarddeveloped by the Advanced Television Systems Committee (ATSC), such ashigh definition television (HDTV), a standard developed by the DigitalVideo Broadcasting (DVB) Project, etc. Advertising, such as anadvertisement and/or a preview of other programming that is or will beoffered by the media sources 112, etc., is also typically included inthe media.

The example media monitoring site 102 also includes meters 106 a, 106 b,106 c, 106 d, 106 e, 106 f to detect and decode watermarks embedded inmedia received at the content receivers 104 a, 104 b, 104 c, 104 d, 104e, 104 f In the illustrated example, the meters 106 a, 106 b, 106 c, 106d, 106 e, 106 f send watermark data to a central facility 114, in otherexamples, the meters 106 a, 106 b, 106 c, 106 d, 106 e, 106 f sendwatermark data back to the media sources 112 or both to the mediasources 112 and the central facility 114.

In examples disclosed herein, to monitor media received by the contentreceivers 104 a, 104 b, 104 c, 104 d, 104 e, 104 f, the meters 106 a,106 b, 106 c, 106 d, 106 e, 106 f of the illustrated example use one ormore physical connections to the content receivers 104 a, 104 b, 104 c,104 d, 104 e, 104 f (e.g., via coaxial RF connection, USB connection, aHigh Definition Media Interface (HDMI) connection, an Ethernet cableconnection, etc.). For example, the meters 106 a, 106 b, 106 c, 106 d,106 e, 106 f process the signals obtained from the content receivers 104a, 104 b, 104 c, 104 d, 104 e, 104 f to detect media and/or sourceidentifying signals (e.g., audio watermarks) embedded in portion(s)(e.g., audio portions) of the media presented by the content receivers104 a, 104 b, 104 c, 104 d, 104 e, 104 f.

In accordance with the present disclosure, meters 106 a, 106 b, 106 c,106 d, 106 e, 106 f and content receivers 104 a, 104 b, 104 c, 104 d,104 e, 104 f are assigned to process broadcasted media. For example, themeter 106 a, connected with the content receiver 104 a assigned toprocess a broadcasted media, detects and decodes watermarks for thebroadcasted media, and does not detect and decode watermarks for adifferent broadcasted media. In such an example, if the content receiver104 a is assigned to receive media broadcasted by channel 1, the examplemeter 106 a only detects watermarks for channel 1, and watermarks notassociated with channel 1 are errant watermarks.

FIG. 2 is an illustration of an example audience measurement systemconstructed in accordance with the teachings of this disclosure toperform watermark detection. In the illustrated example of FIG. 2, anexample media presentation site 202 includes example panelists 204, 206,an example media device 210 that receives media from an example mediasource 212 such as a media broadcaster, and an example meter 214. Theexample meter 214 identifies the media presented by the example mediadevice 210 and reports media monitoring information, including detectedwatermark information, to an example central facility 290, such as anexample audience measurement entity, via an example gateway 240 and anexample network 280. In some examples, the meter 214 is referred to asan audience measurement device.

In the illustrated example of FIG. 2, the example media presentationsite 202 is a room of a household (e.g., a room in a home of a panelist,such as the home of a “Nielsen family”). In the illustrated example ofFIG. 2, the example panelists 204, 206 of the household have beenstatistically selected to develop media ratings data (e.g., televisionratings data) for a population/demographic of interest. In someexamples, an entire family may be enrolled as a household of panelists.That is, while a mother, a father, a son, and a daughter may each beidentified as individual panelists, their viewing activities typicallyoccur within the family's household.

In the illustrated example of FIG. 2, the example media device 210 is atelevision. However, the example media device 210 can correspond to anytype of audio, video and/or multimedia presentation device capable ofpresenting media audibly and/or visually. In some examples, the mediadevice 210 (e.g., a television) may communicate audio to another mediapresentation device (e.g., an audio/video receiver) for output by one ormore speakers (e.g., surround sound speakers, a sound bar, etc.). Asanother example, the media device 210 can correspond to a multimediacomputer system, a personal digital assistant, a cellular/mobilesmartphone, a radio, a home theater system, stored audio and/or videoplayed back from a memory, such as a digital video recorder or a digitalversatile disc, a webpage, and/or any other communication device capableof presenting media to an audience (e.g., the panelists 204, 206).

The media device 210 receives media from the media source 212. The mediasource 212 may be any type of media provider(s), such as, but notlimited to, a cable media service provider, a radio frequency (RF) mediaprovider, an Internet based provider (e.g., IPTV), a satellite mediaservice provider, etc., and/or any combination thereof. The media may beradio media, television media, pay per view media, movies, InternetProtocol Television (IPTV), satellite television (TV), Internet radio,satellite radio, digital television, digital radio, stored media (e.g.,a compact disk (CD), a Digital Versatile Disk (DVD), a Blu-ray disk,etc.), any other type(s) of broadcast, multicast and/or unicast medium,audio and/or video media presented (e.g., streamed) via the Internet, avideo game, targeted broadcast, satellite broadcast, video on demand,etc. For example, the media device 210 can correspond to a televisionand/or display device that supports the National Television StandardsCommittee (NTSC) standard, the Phase Alternating Line (PAL) standard,the Système Électronique pour Couleur avec Mémoire (SECAM) standard, astandard developed by the Advanced Television Systems Committee (ATSC),such as high definition television (HDTV), a standard developed by theDigital Video Broadcasting (DVB) Project, etc. Advertising, such as anadvertisement and/or a preview of other programming that is or will beoffered by the media source 212, etc., is also typically included in themedia.

In examples disclosed herein, an audience measurement entity providesthe meter 214 to the panelist 204, 206 (or household of panelists) suchthat the meter 214 may be installed by the panelist 204, 206 by simplypowering the meter 214 and placing the meter 214 in the mediapresentation site 202 and/or near the media device 210 (e.g., near atelevision set). In some examples, more complex installation activitiesmay be performed such as, for example, affixing the meter 214 to themedia device 210, electronically connecting the meter 214 to the mediadevice 210, etc. The example meter 214 detects exposure to media andelectronically stores monitoring information (e.g., a code detected withthe presented media, a signature of the presented media, an identifierof a panelist present at the time of the presentation, a timestamp ofthe time of the presentation) of the presented media. The storedmonitoring information is then transmitted back to the central facility290 via the gateway 240 and the network 280. While the media monitoringinformation is transmitted by electronic transmission in the illustratedexample of FIG. 2, the media monitoring information may additionally oralternatively be transferred in any other manner, such as, for example,by physically mailing the meter 214, by physically mailing a memory ofthe meter 214, etc.

The meter 214 of the illustrated example combines audience measurementdata and people metering data. For example, audience measurement data isdetermined by monitoring media output by the media device 210 and/orother media presentation device(s), and audience identification data(also referred to as demographic data, people monitoring data, etc.) isdetermined from people monitoring data provided to the meter 214. Thus,the example meter 214 provides dual functionality of an audiencemeasurement meter that is to collect audience measurement data, and apeople meter that is to collect and/or associate demographic informationcorresponding to the collected audience measurement data.

For example, the meter 214 of the illustrated example collects mediaidentifying information and/or data (e.g., signature(s), fingerprint(s),code(s), tuned channel identification information, time of exposureinformation, etc.) and people data (e.g., user identifiers, demographicdata associated with audience members, etc.). The media identifyinginformation and the people data can be combined to generate, forexample, media exposure data (e.g., ratings data) indicative ofamount(s) and/or type(s) of people that were exposed to specificpiece(s) of media distributed via the media device 210. To extract mediaidentification data, the meter 214 of the illustrated example of FIG. 2monitors for watermarks (sometimes referred to as codes) included in thepresented media. In examples disclosed herein, a watermark includes asequence of symbols, with each symbol carrying a portion ofmedia-identifying information which, when concatenated, form a completewatermark. In at least some prior watermarking systems, when any symbolis indecipherable, the entire watermark is discarded. Such an approachcan result in missed watermarks.

Depending on the type(s) of metering the meter 214 is to perform, themeter 214 can be physically coupled to the media device 210 or may beconfigured to capture media signal(s) (e.g., audio) emitted externallyby the media device 210 (e.g., free field audio) such that directphysical coupling to the media device 210 (e.g., media presentingdevice) is not required. For example, the meter 214 of the illustratedexample may employ non-invasive monitoring not involving any physicalconnection to the media device 210 (e.g., via Bluetooth® connection,WIFI® connection, acoustic sensing via one or more microphone(s) and/orother acoustic sensor(s), etc.) and/or invasive monitoring involving oneor more physical connections to the media device 210 (e.g., via USBconnection, a High Definition Media Interface (HDMI) connection, anEthernet cable connection, etc.).

In examples disclosed herein, to monitor media presented by the mediadevice 210, the meter 214 of the illustrated example senses audio (e.g.,acoustic signals or ambient audio) output (e.g., emitted) by the mediadevice 210. For example, the meter 214 processes the signals obtainedfrom the media device 210 to detect media and/or source identifyingsignals (e.g., audio watermarks) embedded in portion(s) (e.g., audioportions) of the media presented by the media device 210. To, forexample, sense ambient audio output by the media device 210, the meter214 of the illustrated example includes an example acoustic sensor(e.g., a microphone). In some examples, the meter 214 may process audiosignals obtained from the media device 210 via a direct cable connectionto detect media and/or source identifying audio watermarks embedded insuch audio signals.

The meter 214 of the illustrated example communicates with a remotelylocated central facility 290, such as the audience measurement entity.In the illustrated example of FIG. 2, the example meter 214 communicateswith the central facility 290 via a gateway 240 and a network 280. Theexample meter 214 of FIG. 2 sends media identification data and/oraudience identification data to the central facility 290 periodically,a-periodically and/or upon request by the central facility 290.

The example gateway 240 of the illustrated example of FIG. 2 can beimplemented by a router that enables the meter 214 and/or other devicesin the media presentation site (e.g., the media device 210) tocommunicate with the network 280 (e.g., the Internet.)

In some examples, the example gateway 240 facilitates delivery of mediafrom the media source(s) 212 to the media device 210 via the Internet.In some examples, the example gateway 240 includes gateway functionalitysuch as modem capabilities. In some other examples, the example gateway240 is implemented in two or more devices (e.g., a router, a modem, aswitch, a firewall, etc.). The gateway 240 of the illustrated examplemay communicate with the network 226 via Ethernet, a digital subscriberline (DSL), a telephone line, a coaxial cable, a USB connection, aBluetooth connection, any wireless connection, etc.

In some examples, the example gateway 240 hosts a Local Area Network(LAN) for the media presentation site 202. In the illustrated example,the LAN is a wireless local area network (WLAN), and allows the meter214, the media device 210, etc., to transmit and/or receive data via theInternet. Alternatively, the gateway 240 may be coupled to such a LAN.

The network 280 of the illustrated example can be implemented by a widearea network (WAN) such as the Internet. However, in some examples,local networks may additionally or alternatively be used. Moreover, theexample network 280 may be implemented using any type of public orprivate network such as, but not limited to, the Internet, a telephonenetwork, a local area network (LAN), a cable network, and/or a wirelessnetwork, or any combination thereof.

The central facility 290 of the illustrated example is implemented byone or more servers. The central facility 290 processes and stores datareceived from the meter(s) 214. For example, the example centralfacility 290 of FIG. 2 combines audience identification data and programidentification data from multiple households to generate aggregatedmedia monitoring information. The central facility 290 generates reportsfor advertisers, program producers and/or other interested parties basedon the compiled statistical data. Such reports include extrapolationsabout the size and demographic composition of audiences of content,channels and/or advertisements based on the demographics and behavior ofthe monitored panelists.

As noted above, the meter 214 of the illustrated example provides acombination of media metering and people metering. The meter 214 of FIG.2 includes its own housing, processor, memory and/or software to performthe desired media monitoring and/or people monitoring functions. Theexample meter 214 of FIG. 2 is a stationary device disposed on or nearthe media device 210. In the illustrated example, the meter 214 isaffixed to a top of the media device 210. However, the meter 214 may beaffixed to the media device in any other orientation, such as, forexample, on a side of the media device 210, on the bottom of the mediadevice 210, and/or may not be affixed to the media device 210. Forexample, the meter 214 may be placed in a location near the media device210.

The meter 214 of the illustrated example detects and decodes watermarkdata for media selected by panelists 204, 206. In some examples, thedetected watermark data may cover a variety of broadcasted media, andthe meter 214 does not identify errant watermarks in the same mannermeters 106 a, 106 b, 106 c, 106 d, 106 e, 106 f of FIG. 1 detect errantwatermarks. For example, meter 214 may need to detect an errantwatermark among dozens of watermarks for a given broadcasted media toidentify a watermark as an isolated watermark.

FIG. 3 illustrates an example audience measurement system 300 fordetecting watermarks embedded in transmitted media. In the illustratedexample of FIG. 3, an audience measurement entity 302 receives detectedwatermark data from an example media broadcaster 310, example mediamonitoring sites 312, 314, and example media presentation sites 316, and318. In some examples, the example audience measurement entity 302corresponds to the example central facility 290 of FIG. 2.

In the illustrated example of FIG. 3, the audience measurement entity302 receives detected watermark data from several different sources, themedia broadcaster 310, the media monitoring sites 312, 314, and themedia presentation sites 316, 318. The example media broadcaster 310detects and reports data on a set of watermarks prior to transmission ofmedia 320. Additionally, the audience measurement entity 302 receivesdata on watermarks received at the example media monitoring sites 312,314 and presented at the example media presentation sites 316, 318. Forexample, one or more of the media monitoring sites 312, 314 could besimilar or identical to the media monitoring site 102 of FIG. 1.Additionally, one or more of the media presentation sites 316, and 318could be similar or identical to the example media presentation site 202of FIG. 2. Additionally, one or more of the media monitoring sites 312,314 and/or the media presentation sites 316, 318 may correspond to mediamonitoring facilities implemented by the audience measurement entity 302and/or another entity or entities to monitor media transmissions (e.g.,broadcasts) in a given geographic area, from one or more sources, etc.

For example, both media monitoring site 312 and media monitoring site314 receive a media 320 from the example media broadcaster 310. In oneexample, the audience measurement entity 302 receives watermark datafrom both the media monitoring site 312 and the media monitoring site314, however media monitoring site 312 indicates isolated watermarks inthe media 320 and media monitoring site 314 does not. In such examples,the audience measurement entity 302 would identify the isolatedwatermarks detected by the example media monitoring site 312 as asite-specific problem. In other examples, the audience measuremententity receives watermark data from both the media monitoring site 312and the media monitoring site 314, and both media monitoring sites 312,314 identify isolated watermarks in the media 320. In such examples, theaudience measurement entity 302 would identify the isolated watermarksdetected by both media monitoring sites 312, 314 as a systemic problemassociated with the media broadcaster 310.

In some examples, both media presentation site 316 and mediapresentation site 318 receive the media 320 from the media broadcaster310. In one example, the audience measurement entity 302 receiveswatermark data from both the media presentation site 316 and the mediapresentation site 318, however media presentation site 316 indicatesisolated watermarks in the media 320 and media presentation site 318does not. In such examples, the audience measurement entity 302 wouldidentify the isolated watermarks detected by the example mediapresentation site 316 as a site-specific problem. In other examples, theaudience measurement entity receives watermark data from both the mediapresentation site 316 and the media presentation site 318, and bothmedia presentation sites 316, 318 identify isolated watermarks in themedia 320. In such examples, the audience measurement entity 302 wouldidentify the isolated watermarks detected by both media presentationsites 316, 318 as a systemic problem associated with the mediabroadcaster 310.

Additionally or alternatively, in some regions, only one mediamonitoring site 312 is within broadcasting range of the example mediabroadcaster 310. As a result, the example audience measurement entity302 receives watermark data from the media monitoring site 312 and themedia presentation site 316, and the media monitoring site 312 indicatesisolated watermarks in the media 320 and the media presentation site 316does not indicate isolated watermarks in the media 320. In such anexample, the audience measurement entity 302 identifies isolatedwatermarks in detected by the media monitoring site 312 as asite-specific problem. In other examples, the audience measuremententity receives watermark data from both the media monitoring site 312and the media presentation site 316, and both media monitoring site 312,and media presentation site 316 identify isolated watermarks in themedia 320. In such examples, the audience measurement entity 302 wouldidentify the isolated watermarks detected by both media monitoring site312, and the media presentation site 316 as a systemic problemassociated with the media broadcaster 310.

FIG. 4 is a block diagram of an example watermark 400 that may beidentified by the example meter 214 of FIG. 2. The example watermark 400of the illustrated example of FIG. 4 includes seven symbols 410, 420,430, 440, 450, 460, 470. However, in some examples, the examplewatermark 400 may include fewer and/or additional symbols. In theillustrated example, each symbol includes seven bits (e.g., with eachbit being a binary one or zero). However, each symbol may take on valuesthat represent any other length and/or size, and/or type(s) ofinformation. For example, each symbol may represent one bit ofinformation, 10 bits of information, 100 bits of information, etc.Furthermore, in the illustrated example of FIG. 4, each symbolrepresents the same number of bits. However, in some examples, differentsymbols may represent different amounts of information. For example, thefirst symbol 410 may represent six bits of information, while the secondsymbol 420 may represent twenty bits of information. In general, smallersymbol sizes may be expected to be more easily distinguished, as thereare fewer data points where an error may occur.

FIG. 5 is an illustration of an example audio waveform 500 andcorresponding portions of time within the audio waveform 500 in whichportions of the example watermark of FIG. 4 are encoded. The examplewaveform 500 of the illustrated example of FIG. 5 is presented along ahorizontal time axis 505, and a vertical amplitude axis 507. The exampleaudio waveform 500 of the illustrated example of FIG. 5 includes a firstexample watermark 508 and the beginning portions of a second examplewatermark 580 transmitted over the time axis 505. In practice, thewatermark(s) may be preceded by a preamble to, for example, identify thetype of watermark about to be conveyed and/or properties of thewatermark. For example, watermark 508 (also referred to as watermark Nin FIG. 4) is preceded by a first example preamble 509, and thewatermark 580 (also referred to as watermark N+1 in FIG. 5) is precededby a second example preamble 582. In the illustrated example of FIG. 5,the watermark 508 and its corresponding preamble 509 are represented byapproximately 1.6 seconds of the audio waveform 500. In examplesdisclosed herein, watermarks begin two seconds apart from each other.That is, the beginning of the watermark 580 starts two seconds after thebeginning of the watermark 508. As noted in connection with FIG. 4, theexample watermarks 508, 580 includes seven symbol segments. In examplesdisclosed herein, each symbol segment and preamble have a duration of192 milliseconds.

In the illustrated example of FIG. 5, the preamble 509 of the firstwatermark 508 is transmitted. Next, the first symbol 510 of the firstwatermark 508 is transmitted, followed sequentially by the second symbol520, the third symbol 530, the fourth symbol 540, the fifth symbol 550,the sixth symbol 560, and the seventh symbol 570. After a delay betweensymbols (approximately one third of a duration of a symbol,approximately 64 milliseconds, etc.), a second preamble 582corresponding to the second watermark 580 is transmitted. The secondpreamble 582 is followed by the first symbol of the second watermark584, the second symbol of the second watermark 586, etc. In someexamples, watermarks are repeated when embedded in the presented media.

FIG. 6 is a block diagram illustrating example information componentsrepresented by the different symbols of the example watermark 400 ofFIG. 4. As noted in connection with FIG. 4, each example watermarkincludes seven symbols that each encode seven bits of information. Intotal, the example watermark 400 includes forty-nine bits ofinformation. In the illustrated example of FIG. 6, the forty-nine bitsinclude a sixteen bit station identifier (SID) 610, followed by areserved bit 620, followed by a two bit distribution channel identifier630, followed by a one bit daylight savings time flag 640, followed by atwenty eight bit timestamp 650.

The example SID 610 identifies the station over which the media isbroadcast. For example, the SID 610 may identify a television station(e.g., channel 7, National Broadcasting Company (NBC), etc.) a radiostation, etc. In the illustrated example of FIG. 6, the SID 610 spansover the first symbol 410 (seven bits), the second symbol 420 (sevenbits), and the first two bits of the third symbol 430. However, the SID610 may be positioned in any other location(s) of the watermark 400.

The example reserved bit 620 is positioned as the third bit of the thirdsymbol 430. However, the example reserved bit 620 may be positioned inthe other location of the watermark. Moreover, in some examples, thereserved bit 620 may be omitted and/or additional bits of the watermark400 may be reserved.

The example two bit distribution channel identifier 630 is representedas the fourth and fifth bits of the third example symbol 430 in theillustrated example of FIG. 6. The example two bit distribution channelidentifier 630 identifies the type of distribution channel over whichthe media is being transmitted for presentation. For example, thedistribution channel identifier 630 may identify that the media is beingbroadcast over a live broadcast system (e.g., a cable televisionnetwork, an IPTV network, etc.) In some examples, the distributionchannel identifier may identify that the media is being distributed in astored format (e.g., in a DVD and/or Blu-ray). In some examples, thedistribution channel identifier may identify that the media is beingstreamed (e.g., transmitted via the Internet).

The example one bit daylight savings time identifier 640 is representedas the sixth bit of the third symbol 430. However, the example one bitdaylight savings time identifier 640 may be located in any otherposition of the watermark. In the illustrated example, the daylightsavings time identifier 640 identifies whether daylight savings time isactive in the region over which the media is being broadcast. Includingthe daylight savings time identifier 640 assists in the identificationof the media based on the SID 610 and the timestamp 650. For example,while a first program may be presented at a first time identified by thetimestamp 650, a second, different, program may be presented at a secondtime one hour later than the first time. The daylight savings timeidentifier 640 enables identification of which media was presented.

The example timestamp 650 of the illustrated example of FIG. 6 isrepresented as the seventh bit of the third symbol 430, the fourthsymbol 440, the fifth symbol 450, the sixth symbol 460, and the seventhsymbol 470. In the illustrated example, the timestamp is a twenty-ninebit representation of the time at which the media was broadcast. Thetimestamp 650, in combination with the SID 610, enables the audiencemeasurement entity to identify the media. In the illustrated example ofFIG. 6, the higher order bits (e.g., bits representing the year, month,and/or day of the timestamp), are represented in the third symbol 430,fourth symbol 440, and fifth symbol 450. The lower order bits of thetimestamp (e.g., bits representing the minutes and/or seconds of thetimestamp) are represented in the sixth symbol 460 and the seventhsymbol 470. As such the higher order bits (e.g., the third symbol 430,the fourth symbol 440, and/or the fifth symbol 450) are not expected tochange frequently (e.g., from one watermark to the next watermarktransmitted approximately two seconds later). However, the lower ordersymbol (e.g., the sixth symbol 460 and the seventh symbol 470) areexpected to change at a more frequent pace. For example, the seventhsymbol 470, which represents the minutes and seconds portion of thetimestamp is expected to change upon every successive watermark. Assuch, between subsequent watermarks, the seventh symbol 470 is notexpected to be the same. As a result, inspection of the seventh symbol470 to identify repeating values is not likely to provide a repeatedresult. Instead, the values of the seventh symbol 470 are likely to bechanged at a regular cadence. To account for such changes, patternmatching may be applied to identify the likely value of the seventhsymbol 470 of the watermark 400.

FIG. 7 illustrates an example block diagram of an example meter 700 todetect watermarks. In some examples, the meter 700 can, for example, beused similarly to the meters 106 a, 106 b, 106 c, 106 d, 106 e, 106 f ofFIG. 1 and/or the meter 214 of FIG. 2. The example meter 700 includes anexample media receiver 710 to receive example external media 712, anexample media identifier 720 having an example symbol decoder 722, anexample symbol buffer 724, an example symbol buffer analyzer 726, and anexample watermark constructor 728, an errant watermark identifier 730,and an example network communicator 740 to communicate with the exampleaudience measurement entity 302. In some examples, the meteradditionally includes a database to store watermark data, the examplemeter 700 could have more components or fewer components.

In the illustrated example, the media receiver 710 receives externalmedia 712. External media 712 can be received via physical connection orindirectly via emitted audio. In some examples, the media receiver 710can employ physical connections including a USB connection, a HighDefinition Media Interface (HDMI) connection, an Ethernet cableconnection, etc. The example media receiver 710 can also use indirectwatermark detection may including a microphone or other audio sensors.

The example meter 700 also includes the media identifier 720. Theexample media identifier 720 obtains, from the media receiver 710, theexample external media 712 and processes the external media 712. In someexamples, the external media 712 is passed through the symbol decoder722. The example symbol decoder 722 identifies and separates the encodedwatermark symbols, decodes the symbols, and places the watermark symbolsin the symbol buffer 724. The example media identifier 720 also includesthe example symbol buffer analyzer 726 to analyze the symbols stored inthe symbol buffer 724. In some examples, the symbol buffer analyzer 726works with the example watermark constructor 728 to identify andconstruct full watermarks.

In the illustrated example, the meter 700 includes the errant watermarkidentifier 730. The errant watermark identifier 730 evaluates the fullwatermarks decoded by the watermark constructor 728 of the mediaidentifier 720, and the errant watermark identifier 730 determines ifthe full watermarks are errant watermarks and/or isolated watermarks.For example, if the example meter 700 is disposed in the example mediamonitoring site 102 of FIG. 1 and assigned to process watermarks fortelevision channel 1 (e.g., would detect the SID 610 corresponding tochannel 1), the errant watermark identifier 730 would identify awatermark as errant if the media identifier 720 decoded a watermark forchannel 2 or as indecipherable. Additionally, if the media identifier720 only decodes one errant watermark during a short time interval(e.g., 30 seconds, 2 minutes, etc.), the errant watermark is furtheridentified as an isolated watermark. Additionally or alternatively, ifthe example meter 700 is disposed in the example media presentation site202 of FIG. 2, the errant watermark identifier 730 would identify errantwatermarks associated with presented media, selected by panelists 104,106.

In some examples, the meter 700 contains a database for storing a set ofwatermark data. In some examples, the database can include watermarkdata having correct watermarks, incomplete watermarks, and/or isolatedwatermarks. In such examples, the set of watermark data stored in theexample database is sent via the example network communicator 740 to theaudience measurement entity 302. In some examples, the set of watermarkdata stored in the database is sent periodically, a-periodically, and/orupon request by the audience measurement entity 302. In the illustratedexample, the meter 700 communicates with the example audiencemeasurement entity 302 of FIG. 3 when a number of isolated watermarks,indicating a problem, meets a threshold. Additionally or alternatively,the network communicator 740 can send watermark data as individualwatermarks or in batches.

FIG. 8 illustrates an example block diagram of an example audiencemeasurement entity 302 processing example watermark data. In theillustrated example of FIG. 8, the audience measurement entity 302includes an example data receiver 810, an example data processor 820, anexample audio engineering problem identifier 830. In some examples, theaudience measurement entity also includes an example errant watermarkidentifier and/or a database. In other examples, the audiencemeasurement entity 302 may have more components or fewer components.

In the illustrated example, the data receiver 810 receives external data812 from the example meter 700 (FIG. 7), which, in some examples, isdisposed at the media monitoring sites 102, 312, 314, and/or mediapresentation sites 202, 316, 318, etc. In some examples, the externaldata 812 includes watermark data including errant watermark data,however, in other examples, the external data 812 includes errantwatermark data exceeding a threshold. Additionally or alternatively, theexample data receiver 810 stores the received watermark data in thedatabase connected with the audience measurement entity 302. In someexamples, the data receiver 810 and the database are separate from theaudience measurement entity 302. In the illustrated example, the datareceiver 810 and the data processor 820 interact without the database.

The example audience measurement entity 302 also includes the dataprocessor 820. The example data processor 820 receives external datafrom the data receiver 810, however in some examples, the data processor820 accesses watermark data stored in the database. In some examples,the data processor 820 performs the general processing of the watermarkdata. For example, the data processor 820 evaluates the watermark dataand associates media presented at example media presentation site 202with panelists 204 and 206 associated with the meter 214 of FIG. 2. Insome examples, the data processor 820 may additionally works as theerrant watermark identifier. In such examples, the data processor 820determines if detected watermarks are errant and/or isolated watermarksby a same or similar process as the errant watermark identifier 730 ofFIG. 7.

In some examples, after isolated watermarks have been identified by thedata processor 820 and/or the example errant watermark identifier 730 ofFIG. 7, the audio engineering problem identifier 850 evaluates theisolated watermarks to determine the existence of an audio engineeringproblem. For example, if a number of isolated watermarks in a second(e.g., longer) measurement interval of time meets a second threshold(e.g., 15 isolated watermarks in 30 minutes, 10 isolated watermarks in 1hour, etc.), the example audio engineering problem identifier 850determines there is a problem with the embedded watermarks. Additionallyor alternatively, the example audio engineering problem identifier 850analyzes isolated watermark data detected by different meters from, forexample, different monitoring sites. For example, the example audioengineering problem identifier 850 may analyze a set of watermark datafrom the media monitoring site 312 and the media monitoring site 314because both sets of watermark data are associated with the same media320. For example, the audio engineering problem identifier 850 candetermine, based on the set of watermark data detected at mediamonitoring sites 312 and 314, that both sites have audio engineeringproblems. In such an example, the audience measurement entity 302 caninform the media broadcaster 310 of an audio engineering problem in thetransmission of media 320.

Additionally, the audio engineering problem identifier can determineproblems as site-specific (e.g., contained to a single mediapresentation site). For example, the audio engineering problemidentifier 850 detects isolated watermarks at the example mediamonitoring site 312. However, if the isolated watermarks do notcorrespond to other media monitoring sites 314 and/or media presentationsites 316, 318, the example audio engineering problem identifier 850 candetermine the example media monitoring site 312 has a site-specificproblem. In other examples, the audio engineering problem identifier 850can determine problems as systemic (e.g., related to the embedding ofthe watermark in the media or related to the transmission of the media).In some examples, the audio engineering problem identifier 850 analyzesa set of watermarks from the media presentation site 316, the mediapresentation site 318, and the media broadcaster 310, because all threesets of watermark data are associated with the same media 320. In suchexamples, the audio engineering problem identifier 850 can determine,based on the set of watermark data detected at the media presentationsite 316, the media presentation site 318, and the media broadcaster 310that all three sites have audio engineering problems and can inform theproducer of the media of an audio engineering problem prior totransmission of media 320.

FIG. 9 is a histogram 900 determined by the example data processor 820(FIG. 8) and/or the errant watermark identifier 730 (FIG. 7) forwatermark data collected at the example media presentation site 202 ofFIG. 2 and the example media presentation sites 316, 318 of FIG. 3. Inthe illustrated example, the histogram 900 includes histogram bins for16 different watermarks included in the data received by the datareceiver for a given first measurement interval described above. In someexamples, the histogram 900 may include a set of watermark data withmore or fewer detected watermarks. In the illustrated example, watermark4 902 a, watermark 7 902 b, watermark 10 902 c, watermark 14 902 d, andwatermark 16 902 e are isolated watermarks as determined by the exampleerrant watermark identifier 840 of FIG. 8. This is because the isolatedwatermarks 902 a, 902 b, 902 c, 902 d, and 902 e have respective numberof occurrences at or below an example first threshold 904 for the firstmeasurement interval of time, as described above. In some examples, thethreshold 804 can be higher or lower than the values shown in theexample of FIG. 9. In some examples, the total number of isolatedwatermarks detected must meet an additional threshold for the exampleaudio engineering problem identifier 850 (FIG. 8) to determine an audioengineering problem.

While an example manner of implementing the meter of FIGS. 1 and 2 isillustrated in FIG. 7, one or more of the elements, processes and/ordevices illustrated in FIG. 7 may be combined, divided, re-arranged,omitted, eliminated, and/or implemented in any other way. Further, theexample media receiver 710, the example media identifier 720, theexample symbol decoder 722, the example symbol buffer 724, the examplesymbol buffer analyzer 726, the example watermark constructor 728, theexample errant watermark identifier 730, the example networkcommunicator 740, and/or, more generally, the example meter 700 of FIG.7 may be implemented by hardware, software, firmware, and/or anycombination of hardware, software, and/or firmware. Thus, for example,any of the example media receiver 710, the example media identifier 720,the example symbol decoder 722, the example symbol buffer 724, theexample symbol buffer analyzer 726, the example watermark constructor728, the example errant watermark identifier 730, the example networkcommunicator 740, and/or, more generally, the example meter 700 of FIG.7 could be implemented by one or more analog or digital circuit(s),logic circuits, programmable processor(s), application specificintegrated circuit(s) (ASIC(s)), programmable logic device(s) (PLD(s)),and/or field programmable logic device(s) (FPLD(s)). When reading any ofthe apparatus or system claims of this patent to cover a purely softwareand/or firmware implementation, at least one of the example datareceiver 810, the example data processor 830, the example errantwatermark identifier 840, the example audio engineering problemidentifier, and/or, more generally, the example audience measuremententity 302 of FIG. 3 is/are hereby expressly defined to include atangible computer readable storage device or storage disk such as amemory, a digital versatile disk (DVD), a compact disk (CD), a Blu-raydisk, etc. storing the software and/or firmware. Further still, theexample meter 700 of FIG. 7 may include one or more elements, processes,and/or devices in addition to, or instead of, those illustrated in FIG.7, and/or may include more than one of any or all of the illustratedelements, processes, and devices.

A flowchart representative of an example method for implementing theexample meter 700 of FIG. 7 is shown in FIG. 10. In this example, themethod may be implemented using machine readable instructions thatcomprise a program for execution by a processor such as the processor1212 shown in the example processor platform 1200 discussed below inconnection with FIG. 12. The program may be embodied in software storedon a tangible computer readable storage medium such as a CD-ROM, afloppy disk, a hard drive, a digital versatile disk (DVD), a Blu-raydisk, or a memory associated with the processor 1212, but the entireprogram and/or parts thereof could alternatively be executed by a deviceother than the processor 1212 and/or embodied in firmware or dedicatedhardware. Further, although the example program is described withreference to the flowchart illustrated in FIG. 10, many other methods ofimplementing the example meter 700 may alternatively be used. Forexample, the order of execution of the blocks may be changed, and/orsome of the blocks described may be changed, eliminated, or combined.

While an example manner of implementing the audience measurement entityof FIG. 3 is illustrated in FIG. 8, one or more of the elements,processes and/or devices illustrated in FIG. 8 may be combined, divided,re-arranged, omitted, eliminated, and/or implemented in any other way.Further, the example data receiver 810, the example data processor 830,the example errant watermark identifier 840, the example audioengineering problem identifier, and/or, more generally, the exampleaudience measurement entity 302 of FIG. 3 may be implemented byhardware, software, firmware, and/or any combination of hardware,software, and/or firmware. Thus, for example, any of the example datareceiver 810, the example data processor 830, the example errantwatermark identifier 840, the example audio engineering problemidentifier, and/or, more generally, the example audience measuremententity 302 of FIG. 3 could be implemented by one or more analog ordigital circuit(s), logic circuits, programmable processor(s),application specific integrated circuit(s) (ASIC(s)), programmable logicdevice(s) (PLD(s)), and/or field programmable logic device(s) (FPLD(s)).When reading any of the apparatus or system claims of this patent tocover a purely software and/or firmware implementation, at least one ofthe example data receiver 810, the example data processor 830, theexample errant watermark identifier 840, the example audio engineeringproblem identifier, and/or, more generally, the example audiencemeasurement entity 302 of FIG. 3 is/are hereby expressly defined toinclude a tangible computer readable storage device or storage disk suchas a memory, a digital versatile disk (DVD), a compact disk (CD), aBlu-ray disk, etc. storing the software and/or firmware. Further still,the example audience measurement entity 302 of FIG. 3 may include one ormore elements, processes, and/or devices in addition to, or instead of,those illustrated in FIG. 3, and/or may include more than one of any orall of the illustrated elements, processes, and devices.

A flowchart representative of an example method for implementing theexample audience measurement entity 302 of FIG. 3 is shown in FIG. 11.In this example, the method may be implemented using machine readableinstructions that comprise a program for execution by a processor suchas the processor 1312 shown in the example processor platform 1300discussed below in connection with FIG. 13. The program may be embodiedin software stored on a tangible computer readable storage medium suchas a CD-ROM, a floppy disk, a hard drive, a digital versatile disk(DVD), a Blu-ray disk, or a memory associated with the processor 1312,but the entire program and/or parts thereof could alternatively beexecuted by a device other than the processor 1312 and/or embodied infirmware or dedicated hardware. Further, although the example program isdescribed with reference to the flowchart illustrated in FIG. 11, manyother methods of implementing the example audience measurement entity302 may alternatively be used. For example, the order of execution ofthe blocks may be changed, and/or some of the blocks described may bechanged, eliminated, or combined.

As mentioned above, the example method of FIGS. 10-11 may be implementedusing coded instructions (e.g., computer and/or machine readableinstructions) stored on a tangible computer readable storage medium suchas a hard disk drive, a flash memory, a read-only memory (ROM), acompact disk (CD), a digital versatile disk (DVD), a cache, arandom-access memory (RAM), and/or any other storage device or storagedisk in which information is stored for any duration (e.g., for extendedtime periods, permanently, for brief instances, for temporarilybuffering, and/or for caching of the information). As used herein, theterm tangible computer readable storage medium is expressly defined toinclude any type of computer readable storage device and/or storage diskand to exclude propagating signals and to exclude transmission media. Asused herein, “tangible computer readable storage medium” and “tangiblemachine readable storage medium” are used interchangeably. Additionallyor alternatively, the example methods of FIGS. 10-11 may be implementedusing coded instructions (e.g., computer and/or machine readableinstructions) stored on a non-transitory computer and/or machinereadable medium such as a hard disk drive, a flash memory, a read-onlymemory, a compact disk, a digital versatile disk, a cache, arandom-access memory and/or any other storage device or storage disk inwhich information is stored for any duration (e.g., for extended timeperiods, permanently, for brief instances, for temporarily buffering,and/or for caching of the information). As used herein, the termnon-transitory computer readable medium is expressly defined to includeany type of computer readable storage device and/or storage disk and toexclude propagating signals and to exclude transmission media. As usedherein, when the phrase “at least” is used as the transition term in apreamble of a claim, it is open-ended in the same manner as the term“comprising” is open ended. Comprising and all other variants of“comprise” are expressly defined to be open-ended terms. Including andall other variants of “include” are also defined to be open-ended terms.In contrast, the term consisting and/or other forms of consist aredefined to be close-ended terms.

FIG. 10 is a flowchart representative of an example computer readableinstructions 1000 that may be executed to implement detection andprocessing of media watermarks by the example meters 106 a, 106 b, 106c, 106 d, 106 e, 106 f of FIG. 1 and/or the example meter 214 of FIG. 2and/or the example meter 700 of FIG. 7. The example method 1000 can beperformed at least in part by computer readable instructions executed bythe example meters 106 a, 106 b, 106 c, 106 d, 106 e, 106 f of FIG. 1and/or the example meter 214 of FIG. 2 and/or the example meter 700 ofFIG. 7. Execution of the example computer readable instructions 1000 isdescribed in connection with the meter 106 a and content receiver 104 aof FIG. 1, but can, in some examples, be applicable to other monitoringarrangements.

Execution of the example computer readable instructions 1000 starts atblock 1002. At block 1002, the example meter 106 a of FIG. 1 receivesexternal media 712 from the media device 210 via the example mediareceiver 710. For example, the external media is received directly, butin other examples, the media is received indirectly.

At block 1004, the example media identifier 720 decodes watermarksymbols embedded in the external media 712 via the symbol decoder 722.For example, decoding the first watermark 508 begins with decoding thefirst symbol 510 of FIG. 5. Additionally, the decoded watermark symbolsare stored in a symbol buffer 724 in the example media identifier 720.In some examples, watermark symbols have 7 bits of information, while inother examples, watermark symbols may have more or fewer bits ofinformation.

At block 1006, the symbol buffer analyzer 726 analyzes the examplewatermark symbols stored in the symbol buffer 724. The example symbolbuffer analyzer 726 analyzes the decoded watermark symbols anddetermines the information transmitted in the watermark (e.g., SIDtimestamp, etc.).

At block 1008, the watermark constructor 728 concatenates the watermarkinformation to reassemble full watermarks. In accordance with theillustrated example of FIG. 6, the watermark constructor 728concatenates the bits for the SID 610, reserved bit 620, distributionchannel identifier 630, daylight savings time identifier 640, andtimestamp 650.

At block 1010, the errant watermark identifier 730 identifies isolatedwatermarks. In some examples, the isolated watermarks are identified asisolated watermarks when the detected watermarks do not correspond tothe example SID 610 (FIG. 6) of the media assigned to the contentreceiver 104 a over a short interval of time (e.g., 30 seconds, twominutes, etc.). In other examples, errant watermarks are compared to,and must satisfy, thresholds.

At block 1012, the example errant watermark identifier 730 determines ifthe number of isolated watermarks satisfies a threshold for indicatingthe presence of an audio engineering problem. In some examples, thethreshold is based on a number of isolated watermarks detected in a timeperiod (e.g., 5 isolated watermarks detected in 10 minutes, 15 isolatedwatermarks detected in 5 minutes, etc.) while in other examples, thethreshold might be a ratio of isolated watermarks to good watermarks(e.g., 5 isolated watermarks to 300 good watermarks, 15 isolatedwatermarks to 150 good watermarks, etc.). In some examples, thesethresholds can be higher or lower. If the number of isolated watermarkssatisfies the threshold, the meter determines there is an audioengineering problem with the media.

FIG. 11 is a flowchart representative of example computer readableinstructions 1100 that may be executed to process sets of watermark dataand identify site-specific and/or systemic watermark problems withbroadcasted media. The example computer readable instructions 1100 canbe performed at least in part by computer readable instructions executedby the example audience measurement entity 302 of FIG. 3 and/or FIG. 8.Additionally, execution of the example computer readable instructions1100 is described in connection with the audience measurement entity 302of FIG. 3, but can, in some examples, be applicable to other dataprocessing facilities, such as the central facility 290.

Execution of the example computer readable instructions 1100 begins atblock 1102. At block 1102, the data receiver 810 of the example audiencemeasurement entity 302 obtains isolated watermark data indicating anaudio engineering problem for media for one or more sites. In somecases, the isolated watermark data includes the isolated watermarks andthe good watermarks, in other examples, the isolated watermark dataincludes an indication of the presence of an audio engineering problemand identifying information of the meter and media. The example isolatedwatermark data may include more or less information.

At block 1104, the audio engineering problem identifier 830 determinesif only one site reached the isolated watermark threshold for the media.If meters at one site have determined there is an audio engineeringproblem associated with the media, and other sites do not detect aproblem with the audio engineering, the example audio engineeringproblem identifier 830 determines the problem is site-specific (Block1106). Otherwise, if meters at two or more sites detect an audioengineering problem, the audio engineering problem identifier 830determines the problem is systemic (Block 1108).

FIG. 12 is a block diagram of an example processor platform 1200structured to execute the example instructions of FIG. 10 to implementthe meter of FIG. 7. The processor platform 1200 can be, for example, aserver, a personal computer, a mobile device (e.g., a cell phone, asmart phone, a tablet such as an iPad™), a personal digital assistant(PDA), an Internet appliance, a DVD player, a CD player, a digital videorecorder, a Blu-ray player, a gaming console, a personal video recorder,a set top box, or any other type of computing device.

The processor platform 1200 of the illustrated example includes aprocessor 1212. The processor 1212 of the illustrated example ishardware. For example, the processor 1212 can be implemented by one ormore integrated circuits, logic circuits, microprocessors or controllersfrom any desired family or manufacturer.

The processor 1212 of the illustrated example includes a local memory1213 (e.g., a cache). The processor 1212 of the illustrated exampleexecutes the instructions to implement the example audio receiver 710,media identifier 720, symbol decoder 722, symbol buffer 724, symbolbuffer analyzer 726, watermark constructor 728, errant watermarkidentifier 730, and network communicator 740. The processor 1212 of theillustrated example is in communication with a main memory including avolatile memory 1214 and a non-volatile memory 1216 via a bus 1218. Thevolatile memory 1214 may be implemented by Synchronous Dynamic RandomAccess Memory (SDRAM), Dynamic Random Access Memory (DRAM), RAMBUSDynamic Random Access Memory (RDRAM), and/or any other type of randomaccess memory device. The non-volatile memory 1216 may be implemented byflash memory and/or any other desired type of memory device. Access tothe main memory 1214, 1216 is controlled by a memory controller.

The processor platform 1200 of the illustrated example also includes aninterface circuit 1220. The interface circuit 1220 may be implemented byany type of interface standard, such as an Ethernet interface, auniversal serial bus (USB), and/or a PCI express interface.

In the illustrated example, one or more input devices 1222 are connectedto the interface circuit 1220. The input device(s) 1222 permit(s) a userto enter data and commands into the processor 1212. The input device(s)can be implemented by, for example, an audio sensor, a microphone, acamera (still or video), a keyboard, a button, a mouse, a touchscreen, atrack-pad, a trackball, isopoint, and/or a voice recognition system.

One or more output devices 1224 are also connected to the interfacecircuit 1220 of the illustrated example. The output devices 1224 can beimplemented, for example, by display devices (e.g., a light emittingdiode (LED), an organic light emitting diode (OLED), a liquid crystaldisplay, a cathode ray tube display (CRT), a touchscreen, a tactileoutput device, a printer and/or speakers). The interface circuit 1220 ofthe illustrated example, thus, typically includes a graphics drivercard, a graphics driver chip, or a graphics driver processor.

The interface circuit 1220 of the illustrated example also includes acommunication device such as a transmitter, a receiver, a transceiver, amodem and/or network interface card to facilitate exchange of data withexternal machines (e.g., computing devices of any kind) via a network1226 (e.g., an Ethernet connection, a digital subscriber line (DSL), atelephone line, coaxial cable, a cellular telephone system, etc.).

The processor platform 1200 of the illustrated example also includes oneor more mass storage devices 1228 for storing software and/or data.Examples of such mass storage devices 1228 include floppy disk drives,hard drive disks, magnetic media, compact disk drives, Blu-ray diskdrives, RAID systems, and digital versatile disk (DVD) drives.

Coded instructions 1232, or computer readable instructions, to implementthe methods represented by the flowcharts of FIG. 10 may be stored inthe mass storage device 1228, in the volatile memory 1214, in thenon-volatile memory 1216, and/or on a removable tangible computerreadable storage medium such as a CD or DVD.

FIG. 13 is a block diagram of an example processor platform 1300structured to execute the instructions of FIG. 11 to implement theaudience measurement entity of FIG. 8. The processor platform 1300 canbe, for example, a server, a personal computer, a mobile device (e.g., acell phone, a smart phone, a tablet such as an iPad™), a personaldigital assistant (PDA), an Internet appliance, a DVD player, a CDplayer, a digital video recorder, a Blu-ray player, a gaming console, apersonal video recorder, a set top box, or any other type of computingdevice.

The processor platform 1300 of the illustrated example includes aprocessor 1312. The processor 1312 of the illustrated example ishardware. For example, the processor 1312 can be implemented by one ormore integrated circuits, logic circuits, microprocessors or controllersfrom any desired family or manufacturer.

The processor 1312 of the illustrated example includes a local memory1313 (e.g., a cache). The processor 1312 of the illustrated exampleexecutes the instructions to implement the example data receiver 810,the example data processor 820, and the audio engineering problemidentifier 830. The processor 1312 of the illustrated example is incommunication with a main memory including a volatile memory 1314 and anon-volatile memory 1316 via a bus 1318. The volatile memory 1314 may beimplemented by Synchronous Dynamic Random Access Memory (SDRAM), DynamicRandom Access Memory (DRAM), RAIVIBUS Dynamic Random Access Memory(RDRAM), and/or any other type of random access memory device. Thenon-volatile memory 1316 may be implemented by flash memory and/or anyother desired type of memory device. Access to the main memory 1314,1316 is controlled by a memory controller.

The processor platform 1300 of the illustrated example also includes aninterface circuit 1320. The interface circuit 1320 may be implemented byany type of interface standard, such as an Ethernet interface, auniversal serial bus (USB), and/or a PCI express interface.

In the illustrated example, one or more input devices 1322 are connectedto the interface circuit 1320. The input device(s) 1322 permit(s) a userto enter data and commands into the processor 1312. The input device(s)can be implemented by, for example, an audio sensor, a microphone, acamera (still or video), a keyboard, a button, a mouse, a touchscreen, atrack-pad, a trackball, isopoint, and/or a voice recognition system.

One or more output devices 1324 are also connected to the interfacecircuit 1320 of the illustrated example. The output devices 1324 can beimplemented, for example, by display devices (e.g., a light emittingdiode (LED), an organic light emitting diode (OLED), a liquid crystaldisplay, a cathode ray tube display (CRT), a touchscreen, a tactileoutput device, a printer and/or speakers). The interface circuit 1320 ofthe illustrated example, thus, typically includes a graphics drivercard, a graphics driver chip, or a graphics driver processor.

The interface circuit 1320 of the illustrated example also includes acommunication device such as a transmitter, a receiver, a transceiver, amodem and/or network interface card to facilitate exchange of data withexternal machines (e.g., computing devices of any kind) via a network1326 (e.g., an Ethernet connection, a digital subscriber line (DSL), atelephone line, coaxial cable, a cellular telephone system, etc.).

The processor platform 1300 of the illustrated example also includes oneor more mass storage devices 1328 for storing software and/or data.Examples of such mass storage devices 1328 include floppy disk drives,hard drive disks, magnetic media, compact disk drives, Blu-ray diskdrives, RAID systems, and digital versatile disk (DVD) drives.

Coded instructions 1332, or computer readable instructions, to implementthe methods represented by the flowcharts of FIG. 11 may be stored inthe mass storage device 1328, in the volatile memory 1314, in thenon-volatile memory 1316, and/or on a removable tangible computerreadable storage medium such as a CD or DVD.

From the foregoing, it will be appreciated that the above disclosedmethods, apparatus, and articles of manufacture detect audio engineeringproblems in media transmitted by media broadcasters and presented atvarious media presentation sites. Audio engineering problems aredetected based on detecting a pattern of isolated or bad watermarks, ora number of isolated/bad watermarks that surpass a threshold. Detectionof audio engineering problems can improve the field of media attributionbased on watermark detection. Quick responsiveness to audio engineeringproblems can improve the quality of watermarks embedded in media.

Although certain example methods, apparatus and articles of manufacturehave been disclosed herein, the scope of coverage of this patent is notlimited thereto. On the contrary, this patent covers all methods,apparatus and articles of manufacture fairly falling within the scope ofthe claims of this patent.

What is claimed is:
 1. An apparatus to detect problems with media, theapparatus including: an errant watermark identifier to identify isolatedwatermarks in a first set of detected watermarks obtained from firstmedia monitored at a first site; and an audio engineering problemidentifier to determine, in response to a first number of isolatedwatermarks identified in the first set of detected watermarks satisfyinga first threshold, that a problem has been detected with the first mediaassociated with the first set of detected watermarks.
 2. The apparatusof claim 1, wherein the errant watermark identifier is to identify afirst one of the detected watermarks as an isolated watermark when acount of the first one of the detected watermarks in the first of thedetected watermarks satisfies a second threshold.
 3. The apparatus ofclaim 1, further including a media receiver to receive the first mediafrom a media source.
 4. The apparatus of claim 1, further including anetwork communicator to transmit an indication of the problem detectedwith the first media to an audience measurement entity.
 5. The apparatusof claim 1, wherein the audio engineering problem identifier is furtherto determine if the problem is site-specific or systemic, wherein theproblem is site-specific if a second number of isolated watermarksidentified for a second site does not satisfy the first threshold, andthe problem is systemic if both the first number of isolated watermarkssatisfies the first threshold and the second number of isolatedwatermarks satisfies the first threshold.
 6. The apparatus of claim 5,wherein the audio engineering problem identifier is further to reportdetection of the problem to a broadcasting source providing the firstmedia if the problem is systemic.
 7. The apparatus of claim 5, whereinthe first site is a media monitoring site and the second site is a mediapresentation site.
 8. A method to detect problems with media, the methodincluding: identifying, by executing an instruction with a processor,isolated watermarks in a first set of detected watermarks obtained fromfirst media monitored at a first site; and determining, by executing aninstruction with the processor, a problem has been detected with thefirst media associated with the first set of detected watermarks inresponse to a first number of isolated watermarks identified in thefirst set of detected watermarks satisfying a first threshold.
 9. Themethod of claim 8, wherein a first one of the detected watermarks isidentified as an isolated watermark when a count of the first one of thedetected watermarks in the first set of the detected watermarkssatisfies a second threshold.
 10. The method of claim 8, additionallyincluding receiving the first media from an assigned media source. 11.The method of claim 8, additionally including transmitting an indicationof the problem detected with the first media to an audience measuremententity.
 12. The method of claim 8, further including determining if theproblem is site-specific or systemic, wherein the problem issite-specific if a second number of isolated watermarks obtained for asecond site does not satisfy the first threshold, and the problem issystemic if both the first number of isolated watermarks satisfies thefirst threshold and the second number of isolated watermarks satisfiesthe first threshold.
 13. The method of claim 12, further includingreporting detection of the problem to a broadcasting source providingmedia corresponding to the first media if the problem is systemic. 14.The method of claim 12, wherein the first site is a media monitoringsite and the second site is a media presentation site.
 15. A tangiblecomputer readable storage medium comprising computer readableinstructions which, when executed, cause a processor to at least:identify isolated watermarks in a first set of detected watermarksobtained from first media monitored at a first site; and determine, inresponse to a first number of isolated watermarks identified in thefirst set of detected watermarks satisfying a first threshold, byexecuting an instruction with the processor, that a problem has beendetected with the first media associated with the first set of detectedwatermarks.
 16. The computer readable storage medium of claim 15,wherein errant watermark identifier is to identify a first one of thedetected watermarks as an isolated watermark when a count of the firstone of the detected watermarks in the first set of the detectedwatermarks satisfies a threshold.
 17. The computer readable storagemedium of claim 15, wherein the instructions when executed, furthercause the processor to transmit an indication of the problem detectedwith the first media to an audience measurement entity.
 18. The computerreadable storage medium of claim 15, wherein the instructions whenexecuted, further cause the processor to determine if the problem issite-specific or systemic, wherein the problem is site-specific if asecond number of isolated watermarks identified for a second site doesnot satisfy the first threshold, and the problem is systemic if both thefirst number of isolated watermarks satisfies the first threshold andthe second number of isolated watermarks satisfies the first threshold.19. The computer readable storage medium of claim 18, wherein theinstructions when executed, further cause the processor to reportdetection of the problem to a broadcasting source providing the firstmedia if the problem is systemic.
 20. The computer readable storagemedium of claim 18, wherein the first site is a media monitoring siteand the second site is a media presentation site.